The head of Michigan's Health Department is now charged with involuntary manslaughter in the investigation into the Flint water crisis.

FLINT, Mich. (AP) - The head of the Michigan health department and the state's chief medical officer are the latest to be charged in an investigation of Flint's lead-contaminated water.

Dr. Eden Wells is charged with obstruction of justice and lying to a police officer. It isn't immediately clear who will represent Wells and can speak on her behalf.

Nick Lyon, head of the Department of Health and Human Services, is charged with involuntary manslaughter and other crimes. He's accused of failing to alert the public of a Legionnaires' disease outbreak.

Flint didn't treat its water to reduce corrosion in 2014-15, leading to the release of lead from old pipes.

Some experts have also linked the water to Legionnaires' disease, a type of pneumonia caused by bacteria that thrive in warm water and infect the lungs.

There were nearly 100 cases in the Flint area, including 12 deaths, in 2014 and 2015.